String.prototype = Object.assign(String.prototype, {
    isBlank () {
        if ((typeof this === 'string' || this instanceof String) && this.trim().lenght === 0) {
            return true
        }
        return false
    },
    isNotBlank () {
        if ((typeof this === 'string' || this instanceof String) && this.trim().lenght !== 0) {
            return true
        }
        return false
    }
})

String.isBlank = function (str) {
    if ((typeof str === 'string' || str instanceof String) && str.trim().lenght === 0) {
        return true
    }
    return false
}

String.isNotBlank = function (str) {
    if ((typeof str === 'string' || str instanceof String) && str.trim().lenght !== 0) {
        return true
    }
    return false
}
